CursorScroll
database parameter
Description
When used with the CursorLock parameter, specifies scrolling
options for cursors in an ODBC data source.
The location of a cursor indicates the current position in the
result set produced by a SQL statement. Scrolling allows a cursor to
move through the data in a result set one row at a time.
Applies to
ODBC (if driver and back-end DBMS support this feature)
Syntax
|
1 |
CursorScroll='scroll_value' |
|
Parameter |
Description |
|---|---|
|
scroll_value |
Specifies the type of scrolling you want to use for
|
Default value
If you do not specify a value for CursorScroll, PowerBuilder
defaults to the cursor scroll settings specified for your ODBC data
source driver.
Usage
For large result sets, it might be impractical to use a
keyset-driven cursor that requires the driver to save keys for the
entire result set. Instead, you can use a mixed cursor by specifying a
32-bit integer value that is the number of rows in your keyset (see
Example 2). This number is typically smaller than the result set. The
default keyset size is 0.
A mixed cursor uses KeySet scrolling within the specified keyset
and Dynamic scrolling outside the keyset.
Examples
Example 1
To set scrolling and locking options for cursors in an ODBC data
source:
-
Database profile
Select Dynamic Scrolling from the Scrolling Options drop-down
list and Optimistic Using Values from the Locking drop-down list on
the Transaction page in the Database Profile Setup dialog
box. -
Application
Type the following in code:
1SQLCA.DBParm="CursorScroll='Dynamic', CursorLock='OptValue'"
Example 2
This example sets the number of rows in the keyset to 100. Assume
that the entire result set has 1000 rows. When the cursor is opened, the
driver saves keys for the first 100 rows of the result set. It then
retrieves the next block of 100 keys until the entire result set is
retrieved.
-
Database profile
Type 100 in the Scrolling Options box on the Transaction page
in the Database Profile Setup dialog box. -
Application
Type the following in code:
1SQLCA.DBParm="CursorScroll=100"
See also